David Moffat

Plymouth Marine Laboratory | PML · Earth Observation Science and Applications

We demonstrate the ability of flow cytometry to determine species specific cellular carbon and chlorophyll content in vivo by using laboratory cultures of phytoplankton encompassing a wide range of cell sizes. When applied to the large Atlantic Meridional Transect flow cytometry dataset, we reveal patterns in the species-specific phytoplankton carb...

Audio segmentation and sound event detection are crucial topics in machine listening that aim to detect acoustic classes and their respective boundaries. It is useful for audio-content analysis, speech recognition, audio-indexing, and music information retrieval. In recent years, most research articles adopt segmentation-by-classification. This tec...

Music production technology has made few advancements over the past few decades. State-of-the-art approaches are based on traditional studio paradigms with new developments primarily focusing on digital modelling of analog equipment. Intelligent music production (IMP) is the approach of introducing some level of artificial intelligence into the spa...

Above‐ground biomass (AGB) is an important metric used to quantify the mass of carbon stored in terrestrial ecosystems. For forests, this is routinely estimated at the plot scale (typically 1 ha) using inventory measurements and allometry. In recent years, terrestrial laser scanning (TLS) has appeared as a disruptive technology that can generate a...

Above Ground Biomass (AGB) is an important metric used to quantify the mass of carbon stored in terrestrial ecosystems. For forests, this is routinely estimated at the plot scale (typically greater or equal to 1 ha) using inventory measurements and allometry. In recent years, Terrestrial Laser Scanning (TLS) has appeared as a disruptive technology...

Audio segmentation and sound event detection are crucial topics in machine listening that aim to detect acoustic classes and their respective boundaries. It is useful for audio-content analysis, speech recognition, audio-indexing, and music information retrieval. In recent years, most research articles adopt segmentation-by-classification. This tec...

In recent years, machine learning has been widely adopted to automate the audio mixing process. Automatic mixing systems have been applied to various audio effects such as gain-adjustment, stereo panning, equalization, and reverberation. These systems can be controlled through visual interfaces, providing audio examples, using knobs, and semantic d...

Mixing music, or music production, is the process of combining a series of different musical tracks together, while applying a range of audio processing to blend the tracks together in a pleasant and aesthetically pleasing way. Music mixing practices require the pleasant combination of all aspects of a musical piece, using a set of engineering tool...

Music and speech detection provides us valuable information regarding the nature of content in broadcast audio. It helps detect acoustic regions that contain speech, voice over music, only music, or silence. In recent years, there have been developments in machine learning algorithms to accomplish this task. However, broadcast audio is generally we...

Segmenting audio into homogeneous sections such as music and speech helps us understand the content of audio. It is useful as a pre-processing step to index, store, and modify audio recordings, radio broadcasts and TV programmes. Deep learning models for segmentation are generally trained on copyrighted material, which cannot be shared. Annotating...

Intelligent Mixing Systems (IMS) are being integrated into mixing workflows, however, there is little discussion around how these technologies are impacting mixing practices. This study explores the possibilities and pitfalls of IMS, by comparing to the use of Computer Assisted Design (CAD) tools in the wider design context. The aim of this paper i...

There is a body of work in the field of intelligent music production, covering a range of specific audio effects. However, there is a distinct lack of any purely machine learning approaches to automatic mixing. This could be due to a lack of suitable data. This paper presents an approach to used human produced audio mixes, along with their source m...

The field of intelligent music production has been growing over recent years. There have been several different approaches to automated reverberation. In this paper, we automate the parameters of an algorithmic reverb, based on analysis of the input signals. Literature is used to produce a set of rules for the application of reverberation, and thes...

It has been well established that equal loudness normalisation can produce a perceptually appropriate level balance in an automated mix. Previous work assumes that each captured track represents an individual sound source. In the context of a live drum recording this assumption is incorrect. This paper will demonstrate approach to identify the sour...

Audio effects are an essential tool that the field of music production relies upon. The ability to intentionally manipulate and modify a piece of sound has opened up considerable opportunities for music making. The evolution of technology has often driven new audio tools and effects, from early architectural acoustics through electromechanical and...

It is not uncommon to hear musicians and audio engineers speak of warmth and brightness when describing analog technologies such as vintage mixing consoles, multitrack tape machines, and valve compressors. What is perhaps less common, is hearing this term used in association with retro digital technology. A question exists as to how much the low bi...

RadioMe aims to perform real-time radio remixing for people with moderate to mild dementia. It would devise a way for them to live independently at homes and reduce the need for carers and family members. Research has suggested that music can help patients regulate emotions such as depression, aggression, and anxiety. Therefore, this project would...

It is not uncommon to hear musicians and audio engineers speak of warmth and brightness when describing analog technologies such as vintage mixing consoles, multitrack tape machines, and valve compressors. What is perhaps less common, is hearing this term used in association with retro digital technology. A question exists as to how much the low bi...

Dynamic range compression (DRC) is a very commonly used audio effect. One use of DRC is to emphasise transients in an audio signal. The aim of this paper is to present an approach for automatically setting dynamic range compression timing parameters, adaptively, allowing parameters to adapt to the incoming audio signal, with the aim of emphasising...

Dynamic range compressors (DRC) are one of the most commonly used audio effect in music production. The timing settings are particularly important for controlling the manner in which they will shape an audio signal. We present a subjective user study of DRC, where a series of different compressor attack and release setting are varied and applied to...

Existing literature has discussed the use of rule-based systems for intelligent mixing. These rules can either be explicitly defined by experts, learned from existing datasets, or a mixture of both. For such mixing rules to be transferable between different systems and shared online, we propose a representation using the Rule Interchange Format (RI...

There are a range of different methods for comparing or measuring the similarity between environmental sound effects. These methods can be used as objective evaluation techniques, to evaluate the effectiveness of a sound synthesis method by assessing the similarity between synthesised sounds and recorded samples. We propose to evaluate a number of...

Aeroacoustics is a branch of engineering within fluid dynamics. It encompasses sounds generated by disturbances in air either by an airflow being disturbed by an object or an object moving through air. A number of fundamental sound sources exist depending on the geometry of the interacting objects and the characteristics of the flow. An example of...

Sound effect libraries are commonly used by sound designers in a range of industries. Taxonomies exist for the classification of sounds into groups based on subjective similarity, sound source or common environmental context. However, these taxonomies are not standardised, and no taxonomy based purely on the sonic properties of audio exists. We pre...

Sound synthesis is the process of generating artificial sounds through some form of simulation or modelling. This article aims to identify which sound synthesis methods achieve the goal of producing a believable audio sample that may replace a recorded sound sample. A perceptual evaluation experiment of five different sound synthesis techniques was...

A real-time physically-derived sound synthesis model is presented that replicates the sounds generated as an object swings through the air. Equations obtained from fluid dynamics are used to determine the sounds generated while exposing practical parameters for a user or game engine to vary. Listening tests reveal that for the majority of objects m...

A real-time sound synthesis model for propeller sounds is presented. Equations obtained from fluid dynamics and aerodynamics research are utilised to produce authentic propeller-powered aircraft sounds. The result is a physical model in which the geometries of the objects involved are used in sound synthesis calculations. The model operates in real...

A real-time physical sound synthesis model of an Aeolian harp is presented. The model uses semi-empirical fluid dynamics equations to inform its operation, providing suitable parameters for users to interact. A basic wind model is included as well as an interface allowing user adjustable parameters. Sounds generated by the model were subject to obj...

Sword sounds are synthesised by physical models in real-time. A number of compact sound sources are used along the length of the sword which replicate the swoosh sound when swung through the air. Listening tests are carried out which reveal a model with reduced physics is perceived as more authentic. The model is further developed to be controlled...

The Web Audio Evaluation Tool is an open-source, browser-based framework for creating and conducting listening tests. It allows remote deployment, GUI-guided setup, and analysis in the browser. While currently being used for listening tests in various fields, it was initially developed specifically for the study of music production practices. In th...

Perceptual listening tests are commonplace in audio research and a vital form of evaluation. While a large number of tools exist to run such tests, many feature just one test type, are platform dependent, run on proprietary software, or require considerable configuration and programming. Using Web Audio, the Web Audio Evaluation Tool (WAET) address...

Sound synthesis can be used as an effective tool in sound design. This paper presents an interactive model that synthesizes high quality, impact-based combat weapons and gunfire sound effects. A procedural audio approach was taken to compute the model. The model was devised by extracting the frequency peaks of the sound source. Sound variations wer...

Reverberation is known to introduce difficulties in audio source separation, and reverse engineering independent sources from a convolutive mixture is one of the toughest challenges within blind source separation. This paper proposes two novel methods that combine dereverberation work with microphone interference reduction. The results are evaluate...

Subgrouping is a mixing technique where the outputs of a subset of audio tracks in a multitrack are summed to a single audio bus. This is done so that the mix engineer can apply signal processing to an entire subgroup, speed up the mix work flow and manipulate a number of audio tracks at once. In this work, we investigate which audio features from...

Audio feature extraction underpins a massive proportion of audio processing, music information retrieval, audio effect design and audio synthesis. Design, analysis, synthesis and evaluation often rely on audio features, but there are a large and diverse range of feature extraction tools presented to the community. An evaluation of existing audio fe...

Perceptual evaluation tests where subjects assess certain qualities of different audio fragments are an integral part of audio and music research. These require specialised software, usually custom-made, to collect large amounts of data using meticulously designed interfaces with carefully formulated questions, and play back audio with rapid switch...